MRI network progression in mesial temporal lobe epilepsy related to healthy brain architecture

We measured MRI network progression in mesial temporal lobe epilepsy (mTLE) patients as a function of healthy brain architecture. Resting-state functional MRI and diffusion-weighted MRI were acquired in 40 unilateral mTLE patients and 70 healthy controls. Data were used to construct region-to-region functional connectivity, structural connectivity, and streamline length connectomes per subject. Three models of distance from the presumed seizure focus in the anterior hippocampus in the healthy brain were computed using the average connectome across controls. A fourth model was defined using regions of transmodal (higher cognitive function) to unimodal (perceptual) networks across a published functional gradient in the healthy brain. These models were used to test whether network progression in patients increased when distance from the anterior hippocampus or along a functional gradient in the healthy brain decreases. Results showed that alterations of structural and functional networks in mTLE occur in greater magnitude in regions of the brain closer to the seizure focus based on healthy brain topology, and decrease as distance from the focus increases over duration of disease. Overall, this work provides evidence that changes across the brain in focal epilepsy occur along healthy brain architecture.

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Accuracy and Efficacy for Robotic Assistance in Implanting Responsive Neurostimulation Device Electrodes in Bilateral Mesial Temporal Lobe Epilepsy

Operative Neurosurgery ◽

10.1093/ons/opx085 ◽

2017 ◽

Vol 14 (3) ◽

pp. 267-272 ◽

Cited By ~ 7

Author(s):

Alvin Y Chan ◽

Lilit Mnatsakanyan ◽

Mona Sazgar ◽

Indranil Sen-Gupta ◽

Jack J Lin ◽

...

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Focal Epilepsy ◽

Mesial Temporal Lobe Epilepsy ◽

Advanced Technology ◽

Robotic Assistance ◽

Mesial Temporal Lobe ◽

Robotic Devices ◽

New Treatment

Abstract BACKGROUND Responsive neurostimulation (RNS) is a relatively new treatment option that has been shown to be effective for patients with medically refractory focal epilepsy when resection is not possible, especially in bilateral mesial temporal onset. Robotic devices are becoming increasingly popular for use in stereotactic procedures such as stereoelectroencephalography, but have yet to be used when implanting RNS devices. OBJECTIVE To show that these 2 forms of advanced technology were compatible and could be used effectively in patient care. METHODS We implanted RNS devices in 3 patients with bilateral mesial temporal lobe epilepsy. Each patient was placed in the prone position, and electrode trajectories were planned via the robotic navigation system via a transoccipital approach. One lead was placed along each amygdalohippocampal complex. A small craniectomy was then created in the parietal region for RNS generator implantation. Actual and expected target locations and distance were calculated for each depth. There were no complications in this group. RESULTS RNS devices with bilateral leads were successfully implanted in all 3 patients, with bilateral mesial temporal lobe onset. Follow-up ranged from 3 to 6 mo, and there were no complications in this group. The median distance between the estimate and actual targets was 2.18 (range = 1.11-3.27) mm. CONCLUSION We show that implanting RNS devices with robotic assistance is feasible with excellent precision and accuracy. The advantages of using robotic assistance include higher flexibility, accuracy, precision, and consistency.

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Decrease of NAA with aging outside the seizure focus in mesial temporal lobe epilepsy—A proton-MRS study at 3 Tesla

Brain Research ◽

10.1016/j.brainres.2007.06.063 ◽

2007 ◽

Vol 1179 ◽

pp. 131-139 ◽

Cited By ~ 8

Author(s):

Franz Riederer ◽

Michal Bittšanský ◽

Eva Lehner-Baumgartner ◽

Christoph Baumgartner ◽

Vladimír Mlynárik ◽

...

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Mesial Temporal Lobe Epilepsy ◽

3 Tesla ◽

Proton Mrs ◽

Seizure Focus ◽

Mesial Temporal Lobe

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Lateralising value of experiential hallucinations in temporal lobe epilepsy

Journal of Neurology Neurosurgery & Psychiatry ◽

10.1136/jnnp-2014-309452 ◽

2015 ◽

Vol 86 (11) ◽

pp. 1273-1276 ◽

Cited By ~ 5

Author(s):

Lukas Heydrich ◽

Guillaume Marillier ◽

Nathan Evans ◽

Olaf Blanke ◽

Margitta Seeck

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Single Photon ◽

Focal Epilepsy ◽

Photon Emission ◽

Mesial Temporal Lobe Epilepsy ◽

Positron Emission ◽

Mesial Temporal Lobe ◽

Deja Vu ◽

Déjà Vu

ObjectivesEver since John Hughlings Jackson first described the so-called ‘dreamy state’ during temporal lobe epilepsy, that is, the sense of an abnormal familiarity (déjà vu) or vivid memory-like hallucinations from the past (experiential hallucinations), these phenomena have been studied and repeatedly linked to mesial temporal lobe structures. However, little is known about the lateralising value of either déjà vu or experiential hallucinations.MethodsWe analysed a sample of 28 patients with intractable focal epilepsy suffering from either déjà vu or experiential hallucinations. All the patients underwent thorough presurgical examination, including MRI, positron emission tomography, single-photon emission CT, EEG and neuropsychological examination.ResultsWhile déjà vu was due to right or left mesial temporal lobe epilepsy, experiential hallucinations were strongly lateralised to the left mesial temporal lobe. Moreover, there was a significant effect for interictal language deficits being more frequent in patients suffering from experiential hallucinations.ConclusionsThese results suggest a lateralising value for experiential hallucinations to the left temporal lobe.

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Comparison of Blood Perfusion Parameters in the Ipsilateral and Contralateral Sides of the Brain in Known Cases of Mesial Temporal Lobe Epilepsy

Iranian Journal of Radiology ◽

10.5812/iranjradiol.107887 ◽

2021 ◽

Vol 18 (2) ◽

Author(s):

Amin Farzadniya ◽

Jafar Mehvari ◽

Reza Basiratnia ◽

Farzad Mehrabi

Keyword(s):

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Blood Perfusion ◽

Mesial Temporal Lobe Epilepsy ◽

Enhanced Mri ◽

Affected Side ◽

Contrast Enhanced ◽

Mesial Temporal Lobe ◽

The Brain ◽

Contrast Enhanced Mri

Background: Temporal lobe epilepsy (TLE) is the most common form of focal seizures. To localize the epileptic site for surgery, different neuroimaging tools are used. Perfusion magnetic resonance imaging (MRI) is one of the modalities used to evaluate the cerebral hemodynamics and localize intracranial neoplasia and cerebrovascular events. Two contrast-based perfusion imaging sequences are described, including dynamic susceptibility contrast-enhanced MRI (DSC-MRI) and dynamic contrast-enhanced MRI (DCE-MRI). The most commonly measured parameters include the relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and mean transit time (MTT). Objectives: This study aimed to evaluate the blood perfusion parameters, such as rCBV and rCBF, in patients diagnosed with mesial temporal lobe epilepsy (MTLE), using DSC-perfusion MRI to determine whether there is a change in these parameters and if this modality can be used to diagnose and localize the epileptic side. Methods: Twenty-two patients, who were diagnosed with TLE clinically and electrophysiologically by a neurologist, were investigated in this study. The patients were examined for the presence of any other lesions, such as tumors or cerebrovascular disease as the exclusion criteria. Perfusion images were processed by the Siemens perfusion software, and the rCBV and rCBF maps were generated based on the gamma variate fit. For qualitative analysis, coronal reconstruction of rCBV and rCBF maps was performed. For quantitative analysis, a single neuroradiologist placed the region of interest (ROI) on the hippocampus and the parahippocampal gyrus on T1W images at the same level of DSC images. After determining the CBV and CBF values relative to the ROI of each side, the asymmetry index (AI) was calculated. Results: In patients with unilateral epilepsy, the blood perfusion parameters in the ipsilateral side of the brain were significantly lower than the contralateral side (P < 0.0001); the mean values of both parameters were significantly lower in the affected side as compared to the opposite side. Conclusions: In patients with TLE, significantly lower blood perfusion parameters in the affected side of the brain can help radiologists and neurologists to lateralize the MTLE side.

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Menstrual cycle worsening of epileptic seizures in women with symptomatic focal epilepsy

Arquivos de Neuro-Psiquiatria ◽

10.1590/s0004-282x2005000500006 ◽

2005 ◽

Vol 63 (3b) ◽

pp. 751-756 ◽

Cited By ~ 27

Author(s):

Ana Carolina Belini Bazán ◽

Maria Augusta Montenegro ◽

Fernando Cendes ◽

Li Li Min ◽

Carlos A.M. Guerreiro

Keyword(s):

Menstrual Cycle ◽

Temporal Lobe Epilepsy ◽

Temporal Lobe ◽

Seizure Frequency ◽

Focal Epilepsy ◽

Epileptic Seizures ◽

Mesial Temporal Lobe Epilepsy ◽

Menstrual Cycles ◽

Medical Appointment ◽

Mesial Temporal Lobe

INTRODUCTION: Hormonal fluctuation is responsible for worsening of epileptic seizures during the menstrual cycle. OBJETIVE: To identify irregularities in the menstrual cycles of women with mesial temporal lobe epilepsy (MTLE) and extratemporal focal epilepsy (ETFE) and correlate the frequency of seizures during the menstrual cycles. METHOD: We evaluated prospectively women in the menacme with MTLE and ETFE. Calendars were provided for these patients, and they were asked to mark their seizure frequency according to the menses. Calendars were reviewed in each routine medical appointment. RESULTS: Thirty-nine patients with MTLE and 14 with ETFE were evaluated. We registered 211 cycles in the patients with MTLE and 49 in those with ETFE. Irregular menstrual cycles were found in 28 (28/39, 71.7%) patients with MTLE and 6 (6/14, 42.8%) with ETFE (p=0.052). Premenstrual seizure worsening was observed in 46 (21.8%) patients with MTLE and 9 (18.3%) with ETFE (p=0.596). Menstrual worsening was observed in 47 (22.2%) patients with MTLE and 15 (30.6%) with ETFE (p=0. 217). Ovulatory worsening was observed in 36 (17%) patients with MTLE and 13 (26.5%) with ETFE (p=0,126). Catamenial worsening was observed in 58 (27.4%) of the patients with MTLE and in 17 (34.7%) of the patients with ETFE (p=0.315). CONCLUSION: There was no difference between the group of patients with MTLE and ETFE regarding the frequency of irregular cycles and seizure worsening during the premenstrual, menstrual, catamenial or ovulatory periods.

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Expression and Potential Function of Plasma Exosomal microRNAs (miR-483-5p, miR-671-5p, and miR-150-3p) in a Mouse Mode and in Mesial Temporal Lobe Epilepsy Patients

10.20944/preprints201612.0151.v1 ◽

2016 ◽

Author(s):

Shaofeng Yan ◽

Guiyang Liu ◽

Wenyan Xie ◽

Dawei Meng ◽

Hua Zhang ◽

...

Keyword(s):

Temporal Lobe Epilepsy ◽

Signaling Pathway ◽

Potential Function ◽

Temporal Lobe ◽

Molecular Mechanisms ◽

Focal Epilepsy ◽

Mesial Temporal Lobe Epilepsy ◽

Nervous System Development ◽

Exosomal Mirnas ◽

Mesial Temporal Lobe

Mesial temporal lobe epilepsy (mTLE) is one of the most common and refractory focal epilepsy syndromes. The molecular mechanisms of TLE are not completely understood. The aim of this study was to investigate the expression and potential function of plasma exosomal miRNAs (miR-483-5p, miR-671-5p, and miR-150-3p) in a mouse mode and in temporal lobe epilepsy patients. It was found that exosomal miRNAs were differentially expressed in three phases of the mouse mode, and exosomal miRNAs were down-regulated in mTLE patients compared with healthy controls. A bioinformatics analysis showed that target genes of exosomal miRNAs were significantly involved in the apoptotic process, cell adhesion, nervous system development, neurotrophin signaling pathway, PI3K-Akt signaling pathway, and metabolic pathways. The areas under the curve of miR-483-5p and miR-150-3p were 0.8714 (sensitivity = 75.00%, specificity = 91.65%) and 0.8213 (sensitivity = 67.50%, specificity = 90.00%), respectively. More importantly, the exosomal miRNAs were significantly associated with clinical parameters. Exosomal miRNAs may have the potential to become diagnostic and therapeutic biomarkers.

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